Effects of food matrix on the prebiotic efficacy of inulin-type fructans: a randomised trial.

Recently there is much debate in the scientific community over the impact of the food matrix on prebiotic efficacy of inulin-type fructans. Previous studies suggest that prebiotic selectivity of inulin-type fructans towards bifidobacteria is unaffected by the food matrix. Due to differences in study design, definitive conclusions cannot be drawn from these findings with any degree of certainty. In this randomised trial, we aimed to determine the effects that different food matrices had on the prebiotic efficacy of inulin-type fructans following a standardised 10-day, 4-arm, parallel, randomised protocol with inulin either in pure form or incorporated into shortbread biscuits, milk chocolate or a rice drink. Similar increases in Bifidobacterium counts were documented across all four interventions using both fluorescence in situ hybridisation (pure inulin: +0.63; shortbread: +0.59; milk chocolate: +0.65 and rice drink: +0.71 (log10 cells/g wet faeces) and 16S rRNA sequencing quantitative microbiome profiling data (pure inulin: +1.21 × 109; shortbread: +1.47 × 109; milk chocolate: +8.59 × 108 and rice drink: +1.04 × 109 (cells/g wet faeces) (all P ≤ 0.05). From these results, we can confirm that irrespective of the food matrix, the selectivity of inulin-type fructans towards Bifidobacterium is unaffected, yet the compositional make-up of the food matrix may have implications regarding wider changes in the microbiota.

Developments in understanding and applying prebiotics in research and practice-an ISAPP conference paper.

AIMS: The concept of using specific dietary components to selectively modulate the gut microbiota to confer a health benefit, defined as prebiotics, originated in 1995. In 2018, a group of scientists met at the International Scientific Association for Probiotics and Prebiotics annual meeting in Singapore to discuss advances in the prebiotic field, focussing on issues affecting functionality, research methodology and geographical differences. METHODS AND RESULTS: The discussion ranged from examining scientific literature supporting the efficacy of established prebiotics, to the prospects for establishing health benefits associated with novel compounds, isolated from different sources. CONCLUSIONS: While many promising candidate prebiotics from across the globe have been highlighted in preliminary research, there are a limited number with both demonstrated mechanism of action and defined health benefits as required to meet the prebiotic definition. Prebiotics are part of a food industry with increasing market sales, yet there are great disparities in regulations in different countries. Identification and commercialization of new prebiotics with unique health benefits means that regulation must improve and remain up-to-date so as not to risk stifling research with potential health benefits for humans and other animals. SIGNIFICANCE AND IMPACT OF STUDY: This summary of the workshop discussions indicates potential avenues for expanding the range of prebiotic substrates, delivery methods to enhance health benefits for the end consumer and guidance to better elucidate their activities in human studies.